Centralize the SELinux chcon helper and use it for downloaded
systemd units, onboot hooks, and apiclient files across EL7 through EL10.
Include chcon in captured EL initramfs images.
Without this fix the onboot services failed to start on SELinux enabled
captured image.
By default, the squashfs file was being cached as well as the contents after extraction.
This is superfluous pressure on the cache of the OS.
However, it does help keep the image afloat through 'confignet', so
leave it on until onboot completes, then reclaim cache and disable further caching.
Markus Hilger
Jarrod Johnson